What is ASTM 516 Gr. 70? ... shai: ASTM A 516 or ASME SA 516 grade is one of the most popular steel grades in market . It is primarily intended for use in welded pressure vessels where notch toughness is important. It comes in four grades 55, 60, 65 & 70. At Oakley Steel we mainly sell 516 gr 60 and 516 gr 70. These grades cover a range of ...[PDF]